竹泉生曰∶余习医术，颇有心得，用集诸前辈名贤之说，略分门户，纂为是书。而余一己之私意为多也。非敢曰命
世，亦不敢自秘。为独得之奇。信吾言者，吾亦愿就正焉，其莫以为然，则吾将启吾后人耳。
竹泉生曰∶女科之难治，与夫造化之妙道，皆在天癸。世莫知其故，是以虽有能为带下医者，但守成法，弗克变通。
其理《经》无明文，昔贤论说难多，然皆未确。余好深思，颇有心得，愿揭着之。（〔批〕《女科集要》自注∶补论、余义，
皆列之上层，以醒阅者之目。）
今夫人身，一小天地也。天一生水，水之数一，人身亦只一水可知也。地二生火，火之数二，人身亦有二火可知也。
人身之一水何在，肾为体而膀胱为用也。水生于肾，藏贮变化，则在膀胱。《经》曰∶膀胱者，州都之官，津液藏焉，
气化则能出矣。
人身之二火何在，心为君火，命门为相火也。命门者，右肾也。昔贤多疑是说，不知睾丸虽二，当交媾泄精时，惟
右丸勃然上掌少腹，发精而鼓注之，于此可验，其为命火之标也。
人所以生，以水火之交也。水交于君火，入心而成血，以灌溉百骸，交于命火，入肾而成精。精者，水之源而命火
之根也。是二者，皆养身之本，人无是不生，故曰∶人未有不水火相交而生者。
然此皆以一水而分交于二火者也。童男当五六岁，或八九岁时，见美好女子，其心知好之矣。然及其昵偎而相搂抱
也，其阳物安然而不动，是君火动而相火静也。吾以是知其君相火未尝相谋也。无故而为之摩弄之，则其物亦能跃然而
挺起，然其心不知何以故也。是相火动而君火静也。吾以是更知其君相火不相谋也。此之谓一水分交于于二火耳。
逮夫男子十六，女子十四，则君相二火相会，入于胞宫，而合交于一水矣。二火合交于一水，于是乎始成天癸，君
欲取是水以为血，故水从君火之化而为血之色；相又欲取是水以为精，故水又从相火之化而为精之质。然既不成精，又
不成血，君舍之，相亦舍之，则是人身之废材，而不足以有养身之益矣，故及其盈也而泄之。故曰∶二火合交于一水，
是成天癸。
当斯时也，君相二火，合于一水，生生之气，循环而发，化育之意，油然而兴，心有爱慕，则相火亦随之而动矣。
相火勃不自遏，则虽无所怀念，亦且至无端而生遐想，则是相火掣动君火也。明乎此者，不独有益于医理，慎独诚意之
功，可以思过半矣。
然而男子之亦有天癸，何以不外见也？男子秉阳道而生，本乎天，天行健，健则不息，而阳道以气胜，故其天癸随
化为精也，虽亦设之天癸，其色不赤。女子秉阴道而生，本乎地，地浓重而不变，而阴道以血胜，故其天癸既成赤色，
不能复返其本。至于女子外泄，而男子独否者，交媾之道。男子无所取，女子有所茹，是亦退者进之益者损之之义也。
观夫新婚士女，男必少瘦，妇必加肥，亦可以明其道矣。
二火合交于一水，有天地交泰，水火既济之义。于道又为两仪返本，重混一而成太极之象。故袁了凡曰∶斯时也，
顺而施之则成胎，逆而取之则成丹，盖此意也。然左道邪术，君子弗言也。
欲动情胜，不自制之害也。故能澄水制火者，可造道入德。而黄老之道，亦生于是矣。
尝闻者有武弁，嬖一男外家，廿年，遂以月行经如妇人，事虽无考，然亦理之所固有也。不胜客阳反为所制，积久而
消，化为纯阴，故竟为外家妇之道矣。质之变迁，气之移易，亦理之常，附是论之。
Zhuquansheng said: I have studied medicine and gained considerable insight. I have collected the theories of past masters, roughly categorized them by school, and compiled this book. It contains much of my personal opinion. I dare not claim to be a savior of the world, nor do I wish to keep these secrets as a unique discovery. Those who believe my words, I am willing to accept correction; those who do not agree, I shall leave this for my descendants.
Zhuquansheng said: The difficulty in treating gynecological diseases and the profound mysteries of creation both lie in *Tian Gui* (Heavenly Water / Reproductive Essence). The world does not know the reason for this. Therefore, although there are physicians skilled in treating leukorrhea, they merely adhere to established methods without flexibility. This principle is not explicitly stated in the *Classic of Internal Medicine* (*Huangdi Neijing*), and previous scholars' discussions were mostly inconclusive. I enjoy deep contemplation and have gained insights, so I wish to reveal this theory. ([Commentary] *Summary of Gynecological Essentials* self-note: Supplementary discussions and additional meanings are listed at the upper level to catch the reader's eye.)
Now, the human body is a small heaven and earth. Heaven generates Water first; the number of Water is one, so it can be known that the human body has only one Water. Earth generates Fire second; the number of Fire is two, so it can be known that the human body has two Fires. Where is the one Water in the human body? The Kidney is the substance (Ti), and the Bladder is the function (Yong). Water originates from the Kidney, but its storage and transformation occur in the Bladder. The *Classic* says: "The Bladder is the official of the provincial capital; fluids are stored here, and through Qi transformation, they are excreted."
Where are the two Fires in the human body? The Heart is the Sovereign Fire, and the Mingmen (Gate of Life) is the Ministerial Fire. The Mingmen is the right Kidney. Past scholars often doubted this view. They did not realize that although there are two testicles, during intercourse and ejaculation, only the right testicle rises vigorously to the lower abdomen, ejecting semen and pulsating. From this, it can be verified that it is the manifestation of the Fire of the Mingmen.
Human life exists because of the interaction between Water and Fire. When Water interacts with the Sovereign Fire, it enters the Heart and becomes Blood, irrigating the entire body. When Water interacts with the Ministerial Fire, it enters the Kidney and becomes Essence. Essence is the source of Water and the root of the Ministerial Fire. These two are the foundation of nourishing the body. Without them, humans cannot survive. Thus it is said: No human survives without the interaction of Water and Fire.
However, this refers to one Water interacting separately with two Fires. When boys are five or six years old, or eight or nine, seeing beautiful women, their hearts know they like them. But when they embrace closely, the penis remains calm and motionless. This indicates that the Sovereign Fire moves while the Ministerial Fire is still. From this, I know that the Sovereign and Ministerial Fires do not conspire together. If touched or played with without cause, the penis may rise suddenly, but the mind does not know why. This indicates that the Ministerial Fire moves while the Sovereign Fire is still. From this, I further know that the Sovereign and Ministerial Fires do not interact. This is called one Water interacting with two Fires.
When boys reach sixteen and girls fourteen, the Sovereign and Ministerial Fires meet, enter the Uterus (Bao Gong), and combine with the one Water. When the two Fires combine with the one Water, *Tian Gui* begins to form. The Sovereign Fire desires to transform this Water into Blood, so the Water takes on the color of Blood under the influence of the Sovereign Fire. The Ministerial Fire also desires to transform this Water into Essence, so the Water takes on the quality of Essence under the influence of the Ministerial Fire. If it forms neither Essence nor Blood, and is abandoned by both the Sovereign and Ministerial Fires, it becomes waste material in the body, useless for nourishment. Therefore, it is expelled when full. Thus it is said: The combination of two Fires with one Water constitutes *Tian Gui*.
At this time, the Sovereign and Ministerial Fires combine with the one Water. The vital energy of generation circulates and arises; the intent of creation emerges spontaneously. If the heart harbors affection, the Ministerial Fire moves accordingly. If the Ministerial Fire erupts uncontrollably, even without specific thoughts, endless fantasies arise. This shows the Ministerial Fire pulling the Sovereign Fire. Understanding this benefits not only medical theory but also the practice of mindfulness and sincerity in self-cultivation.
Why does men's *Tian Gui* not manifest externally? Men are born following the Yang Dao, rooted in Heaven. Heaven's movement is vigorous and unceasing, and Yang prevails through Qi. Thus, men's *Tian Gui* transforms into Essence. Although *Tian Gui* is present, its color is not red. Women are born following the Yin Dao, rooted in Earth. Earth is heavy and unchanging, and Yin prevails through Blood. Thus, women's *Tian Gui* becomes red and cannot return to its original state. As for why women menstruate externally while men do not, it lies in the way of intercourse. Men take nothing; women receive. This follows the principle that what retreats advances, and what increases diminishes. Observing newlyweds, men tend to lose weight slightly, while women gain weight, which clarifies this principle.
The combination of two Fires with one Water carries the meaning of Heaven and Earth communicating (Jiao Tai) and Water and Fire achieving balance (Ji Ji). In Daoism, this is also described as the Two Modes returning to their origin, mixing again to form the image of the Great Ultimate (Taiji). Therefore, Yuan Liaofan said: At this time, following it leads to conception; reversing it leads to the formation of the Elixir. This is the meaning. However, heterodox arts are not spoken of by gentlemen.
Desire moving and emotion prevailing, if not self-controlled, causes harm. Therefore, those who can clarify Water and control Fire can attain the Dao and virtue. The Way of Huang-Lao also arises from this.
I once heard of a military officer who favored a male concubine for twenty years, eventually menstruating monthly like a woman. Although this event cannot be verified, it is inherent in reason. Unable to withstand the guest Yang, he was controlled by it. Over time, it diminished and transformed into pure Yin, thus becoming the path of a female concubine. Changes in substance and shifts in Qi are also normal principles. I attach this discussion here.